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EFI problem?

I did not experience this with my road king with the same setup it ran great.

Tell me more about the bike you had that did NOT experience a problem at high altitude. What year, what fuel management, stage 1, pipes, did it have stock cams, A/C.

Also what is the altitude of where you live VS where you were at in the Rockies. Would you know what altitude you were at in feet when you had the worst time with a power issue during your trip.

Lastly, On the bike you did not have this problem with, did you take it to the SAME altitude when it "ran great".
 
The bike we rode was a '01 flhrci, I installed a power commander, V&H true duels, a ness big sucker air cleaner and stock mufflers with the baffles drilled out. The same setup thats on the '06 flhtc except the brand name of the air cleaner. The road where the comparison would be the same is the Beartooth highway, thats about 14,000ft. el. with the '06 I had trouble all the way up, very bad at the summit.
Where I live is just about 200ft. above sea level.

The injectors were changed about 6 months after I bought the bike, I think they went to 26 degree angle
 
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Your bike running the way it does really does not surprise me. What surprises me more was your 2001 bike did not experience the problem (at least to any great degree).

The entire process of a piston driven engine is based on atmospheric pressure. Without it you could not fill the cylinders with air. At sea level we have 14.7 lbs of air pressure trying to fill or push air into the cylinder. The throttle body, cylinder valves, intake manifold and all the curves and restrictions along the way impede the flow. Without that 14.7 lbs of force behind the air, the cylinders would not fill.

At 14,000 ft above sea level that 14.7 lbs of atmospheric pressure needed becomes just over 8 lbs. All that missing oxygen leaves you no chance for developing any power.
I really would not expect to see better performance. The REAL question should be why didn't the 2001 experience the decline in power. Maybe back in 2001 the cam profile allowed better VE,, I don't know.
Anything that restricts VE would cause what you recently felt.

Just to give you an idea how much 14,000 ft in elevation hurts VE, you would have had to have a supercharger on your bike with almost 7 lbs of boost pressure to make up for that elevation. That is insane. It's almost 1/2 an atmosphere.

Theoretically at 17,000 ft you should see a drop of 50% in power.
 
The bike we rode was a '01 flhrci, I installed a power commander, V&H true duels, a ness big sucker air cleaner and stock mufflers with the baffles drilled out. The same setup thats on the '06 flhtc except the brand name of the air cleaner. The road where the comparison would be the same is the Beartooth highway, thats about 14,000ft. el. with the '06 I had trouble all the way up, very bad at the summit.
Where I live is just about 200ft. above sea level.

The injectors were changed about 6 months after I bought the bike, I think they went to 26 degree angle

I'm just going to throw this out as a thought. Your 01 is Magnetti-Marelli(ALPHA-n) and it operates off your throttle. Your 06' is Delphi and it operates off of your MAP sensor which plays a major role in the operation of the Delphi system. It senses the difference in atmospheric pressure with elevation changes. If it is operating correctly, you should be able to go from 0ft to 10,000ft and the ecm would compensate for the change. Maybe the MAP sensors not up to snuff. Just a thought.
 
Great idea but lets analyze it. (rough numbers for illustration)

Lets say at sea level (14.7 atmospheric pounds of pressure) your A/F ratio is 13.5 to 1. Now you go to 17,000 ft above sea level where the atmospheric pressure is 7.5 lbs per square inch. Even if you were to make your A/F ratio exactly the same as it was at sea level, your cylinders would only be charged up or filled to 1/2 of what they were before. The Density of the air is 1/2 what it was. The A/F could be the exact same number (13.5 to 1) but the problem is there is only 1/2 the oxygen and 1/2 the fuel now going into the cylinder. The compressed oxygen & fuel charge will be 1/2 as much as before.

This is really the principle behind supercharging or stuffing a cylinder.
 
Great idea but lets analyze it. (rough numbers for illustration)

Lets say at sea level (14.7 atmospheric pounds of pressure) your A/F ratio is 13.5 to 1. Now you go to 17,000 ft above sea level where the atmospheric pressure is 7.5 lbs per square inch. Even if you were to make your A/F ratio exactly the same as it was at sea level, your cylinders would only be charged up or filled to 1/2 of what they were before. The Density of the air is 1/2 what it was. The A/F could be the exact same number (13.5 to 1) but the problem is there is only 1/2 the oxygen and 1/2 the fuel now going into the cylinder. The compressed oxygen & fuel charge will be 1/2 as much as before.

This is really the principle behind supercharging or stuffing a cylinder.

Hoople, everything you say happens to all vehicles whether it be car, bike or plane. But, 01RK said his 01 ran fine and only the 06 had problems. Maybe, both lacked power at elevation, but only one ran poorly. I'm also guessing that 01RK's engine was running rich. When the manifold sensor is working properly(leans the engine at higher elevation) the expected MPG may actually increase, due to the engine running leaner.
01RK - A quick way to check the MAP sensor is to measure the voltage between the sensor and ground with the engine not running and you should see between 3.5 to 5 volts. Hot idle is .5 to 1.5 volts. Any reading of "0" volts or over 5 volts would indicate a problem.
 
Wouldn't a faulty map sensor have showed up when I checked the dtc's?
I will check this out.
Just returned from a local shop, spoke with owner about the problem, he indicated the sensors should have made some compensation for the A/F.
My '01 never ran out of throttle in the mtn's always had enough to get up those big ones.
 
When the manifold sensor is working properly(leans the engine at higher elevation) the expected MPG may actually increase,

Ok. And after you lean it out, then what? At 14,000 ft there is less Oxygen. That's all she wrote. Your not going to create ENERGY using gasoline alone.
 
Ok. And after you lean it out, then what? At 14,000 ft there is less Oxygen. That's all she wrote. Your not going to create ENERGY using gasoline alone.

Hoople, you seem to be hung up on something. Perhaps, you should reread what 01RK is saying. He has 2 bikes, one works fine, one doesn't. If he had a problem on one bike at SEA LEVEL, it would still be - one works , one don't. Sooo, he'd like to find out why his o6 won't run the way the his 01 does. If you have any ideas on how to fix his 06 bike (aside from your suggestion of the SUPERCHARGER), I'm sure he's open to any fixes.
 
Sooo, he'd like to find out why his o6 won't run the way the his 01 does.

No I do not have any fixes or suggestions for the '06. None at all. The reason is because it's "the other way around" for me. I DO Know why his '06 does not run well but I DON'T know why his '01 ran fine..

I won't buck the laws of Physics. I accept the 2006 running poor. I would expect nothing more from an engine having 9 psi of atmospheric pressure. To me, "They all would do it"
Think about it. If you have 76 H.P. at sea level, what can you possibly have at 14,000 ft? Maybe 40? Absolute Tops 45. How is the bike going to feel.?

My amazement is with the '01. The claim is the bike ran fine at 14,000 ft. I just can't see how that was possible. I am sorry but I would have to see & feel that with my own eyes. These engine management systems are Alpha-N systems. They don't have mass airflow sensors. The '01 had nothing going for it that the '06 did not have.

I can only come up with 1 way to explain it. There is 5 years of EPA regulations between these two bikes. If it really ran THAT MUCH better, the '01 must have had a better profile cam for better VE (more overlap, etc) because emissions allowed it. Don't know if all the performance came from the cam alone,,but the VE of the '01 engine HAD to be better. Why I don't know. I don't have an answer for that question.

At this moment we are comparing events that happened using "seat of the pants" measuring instruments only. We are comparing an occurrence with no real data to back it up. Heck, maybe your right. Maybe the '06 does have a problem, but I have no clue where to start with it. Sorry but I have no more to contribute to this one.
 
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